Hi Stewart:

You are asking all good questions! Unfortunately, back in the era of the mono "1812" master tapes, 
Audio Devices put batch numbers only on crates containing the individual tape reels. In fact, in 
that era, they often didn't have any Audiotape branding on the brown-cardboard packaging for bulk 
sales to studios and other professional/industrial buyers. The pretty boxes were mainly for 7" reels 
for sale to consumers.

It's entirely possible that the "1812"/"Capriccio" tapes were from different batches. Why? The 
"Capriccio" is a first-generation edited master made at the original recording session in 
Minneapolis in 1954. The "1812" and the narration were produced at Fine Sound Studios because the 
"1812" is a mixed production -- original music score, cannon and bells. All of this is explained in 
Deems Taylor's excellent narration. In any case, the master tape was recorded at a different time 
and different location from the component "session" tapes, and would thus most likely be from a 
different batch. What I was getting at with John Schroth is that it's strange how the occasional 
batch of Audiotape (only 1/4", in my experience) goes bad like this, while most don't.

Regarding Richard's comment about iron, I would guess that 3M/Scotch, Kodak and Audio Devices all 
had different suppliers of iron oxide for their tape formulations. Their plants were located in 
different places, and back in that time there were many iron mines and many producers of iron 
products in the US. Plus, I assume everyone had different oxide formulations. You can listen to each 
kind of tape and the hiss is different. So, if iron has something to do with vinegar syndrome, each 
oxide would have a different net effect on whether it happens and how fast it happens.

Finally -- Kodak tape. Every reel I've seen has been edge-warped and shrunken. I've only had to play 
a few for transfer jobs. In all cases, they're required my gauze in the head can brute-force 
approach on an Ampex AG-440. The gauze pushes the warped tape against the play head (not good for 
the head at all). An AG-440 drive is brute-forceful enough to overcome the added friction. None of 
these tapes were high-fidelity music masters but all were valuable to the client. Kodak had really 
pretty packaging. It's too bad their tape formulation was doomed from the start.

-- Tom Fine

----- Original Message ----- 
From: "Stewart Gooderman" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, March 01, 2015 4:19 PM
Subject: Re: [ARSCLIST] Distressing data point for upcoming ARSC tape playback workshop

> What I say here are words of a layperson with respect to restoration, but I am somewhat familiar 
> with organic polymerization being an contact lens practitioner.
> Tom, do you know whether the two recordings were done on the same batch of tape? Because if they 
> were different, they a) could have been polymerized differently, and/or b) could have been handled 
> differently prior to Mercury receiving and using them to record on. In the short run that might 
> not make a difference, but in the long run that could have a profound effect.
> Rigid contact lenses are made from buttons that are cut from long rods of plastic. It is well 
> known that the quality of the polymerization at one end of the rod can be different that at the 
> other end and this can lead to differences in quality when the contact lens is finished.
> Cellulose can consist of hundreds to thousands of D-glucose units, and so cellulose is not 
> cellulose. It’s makeup can vary, the quality of the polymerization can vary, and it’s subsequent 
> breakdown from heat and moisture can vary.
> I’ve even seen things like this with spectacles, when a lens is cut very slightly off. It fits 
> into the plastic frame well enough when new, but in 2+ years you can see the lens buckling inside 
> the eyewire.
> Again, I’m not an expert here, nor am I a chemical engineer. Just food for thought.
> DrG
>> On Mar 1, 2015, at 11:43 AM, Tom Fine <[log in to unmask]> wrote:
>> Interesting case in point  -- the 1956 1/4" master tapes for the mono Mercury "1812 Overture." 
>> Side 1, the overture and the spoken narration by Deems Taylor, the master tape is a mess. It's 
>> badly edge-warped and smells of vinegar. Side 2, the Capriccio Italien, the master tape is in 
>> perfect condition. Both Audiotape, both made at the same time. Both tapes have been treated and 
>> stored the same because they are of one single album. Why has one fallen apart and the other not? 
>> Very strange! Have you seen any such things with acetate media in the Hollywood vaults?
>> -- Tom Fine